Economic Development and the Escape from High Mortality pdf

Economic Development and the Escape from High Mortality JAVIER A. BIRCHENALL * University of California, Santa Barbara, CA, USA Summary. — This paper studies the characteristic features of the escape from high mortality as re- corded from the historical experience of Northwestern Europe and from the current experience of less developed countries. The paper documents stylized facts of mortality change and measures the contribution of economic development, represented by income per capita, to the mortality decline during the second half of the 20th century. The paper argues that improvements in economic con- ditions since the 18th century are an important factor behind the decline in death rates in developed countries and in the subsequent reduction of death rates in less developed countries. We show that economic development lowers mortality through differential effects in infectious disease mortality and that quantitatively, income growth is able to account for between one-third and one-half of the recent mortality decline. Ó 2007 Elsevier Ltd. All rights reserved. JEL classification — I12, O11, O33 Key words — mortality, economic development, developed and less developed countries 1. INTRODUCTION Death is inevitable and irreversible, but the last three centuries have seen remarkable pro- gress in the reduction of human mortality. The mortality of pre-modern populations var- ied considerably, but a simple comparison typ- ically finds that the average life expectancy at birth has roughly doubled during the last three centuries. The decline in death rates has pro- ceeded at non-uniform rates, but it has affected all geographic areas and all demographic groups in the world. Today, even the countries with the highest death rates, such as those in sub-Saharan Africa, are above the historical mean despite the HIV/AIDS epidemic that has reduced the life expectancy at birth of their inhabitants by at least 10 years. The list of explanations offered as to why mortality has declined is not a short one, and a comprehensive analysis is likely to suggest multiple factors and mutual reinforcements. The spectacular mortality decline in less devel- oped countries during the second half of the 20th century has generated the impression that the mortality decline was simply due to modern medicine and innovations in medical science. However, most of the explanations based on modern medicine could not have played a large role in the mortality decline of developed coun- tries, since the fundamental innovations that served to control the spread of infectious dis- ease originated when the mortality decline was already in progress (McKeown, 1976). Of the major breakthroughs in disease control listed in Easterlin (2004, Tables 7.1–7.2), only vaccinations against smallpox took place be- fore the mid-19th century. 1 Public health efforts through sanitation and measures directed to lower the exposure to infectious diseases played an important role in the acceleration of the mortality decline of developed countries since the last quarter of the 19th century (i.e., Cutler & Miller, 2005) * This paper is based on my dissertation research. I am especially indebted to Professor Robert Fogel for many valuable suggestions. I have also benefited from com- ments by seminar participants at numerous locations and from detailed suggestions from three anonymous reviewers of this Journal. Financial support from Banco de la Repu ´ blica Colombia is gratefully acknowledged. Final revision accepted: June 13, 2006. World Development Vol. 35, No. 4, pp. 543–568, 2007 Ó 2007 Elsevier Ltd. All rights reserved 0305-750X/$ - see front matter doi:10.1016/j.worlddev.2006.06.003 www.elsevier.com/locate/worlddev 543 and in the escape from high mortality in less developed countries, but these efforts mainly benefited urban populations at first. Prior to the public health intervention in cities, rural areas of Northwestern Europe and North America achieved sustained reductions in mor- tality from infectious diseases sensitive to nutri- tional status. Attention has turned, once again, to economic development as a factor in the es- cape from high mortality. 2 Empirical evidence supports the idea that improvements in economic conditions in the 18th century were fundamental in the decline in death rates in developed countries and an important factor in the subsequent reduction of death rates in less developed countries. Fogel (1994, and elsewhere) shows how improve- ments in food availability and nutritional status translate into lower mortality risks by improve- ments in body composition. As he points out, well-nourished and healthy children develop better cells and organs and reach higher heights and lower mortality. In the secular decline, Fo- gel (1994) argues, nutrition and factors associ- ated with body composition explain most of the actual mortality decline prior to 1870 and half of it after 1870. For less developed countries, Preston (1980) has shown that economic development, mea- sured by higher income per capita, is able to ex- plain about 30% of the modern increase in life expectancy during 1940–70. Although Preston (1975) showed that economic development could only account for as much as 30% of the mortality improvements in the world from the 1930s to the 1960s, aggregate income gains were the dominating factor in explaining mor- tality decline during 1960s–70s (Preston, 1985). Similar quantitative effects were found by Pritchett and Summers (1996) and Easterly (1999) through instrumental variables (IV) esti- mation rather than through the OLS estimates employed by Preston (1975, 1980, 1985). The role of economic development and changes in public health (broadly defined) as the fundamental aspects in low mortality leave little or no room for additional explanations. Some, based on genetic factors, either in hu- mans or in the pathogens responsible for high mortality, are available, but they seem rather unlikely (although a decline in virulence ap- pears to have affected scarlet fever, see McKe- own, 1976). Kunitz (1983) argues convincingly against genetic change in the pathogens respon- sible for high mortality since virulence is still high in many poor countries. In addition, the change in mortality during the last three centu- ries has been so fast and so widely distributed that genetic changes in humans are incompati- ble with such mortality trends. 3 In this paper, we study the characteristic features of the escape from high mortality as recorded from the historical experience of Northwestern Europe and from the current experience of less developed countries. Based on historical and current evidence, we docu- ment the basic facts of mortality change. We show that the mortality transition has striking similarities in terms of the demographic groups mostly benefitting from the decline and the geo- graphic areas that were first affected by low mortality. The changes have important implica- tions for recent theoretical attempts to study modern population and economic changes and for the ongoing debate on the role of eco- nomic factors in the mortality decline. The second objective of the paper is to mea- sure the contribution of economic develop- ment, represented by income per capita, to the mortality decline in the second half of the 20th century. Using aggregate measures of mortality, we are able to avoid many of the dif- ficulties inherent in individual estimates but face other statistical problems such as endoge- neity. Economic development is likely to reduce mortality and morbidity even by simple Mal- thusian channels, but there is no doubt that the reduction in mortality has translated into higher income per capita. Consequently, OLS estimates of the effects of income on mortality are likely to provide a biased measure of the ef- fect of economic development in the escape from high mortality. To obtain estimates of the effect of income on mortality rates that are not affected by the pres- ence of endogeneity, we rely on IV constructed from economic variables and residuals. As the validity of instruments often employed in the economic growth literature (i.e., Easterly, 1999; Pritchett & Summers, 1996) is not unproblematic, we also rely on the dynamic structure of the model using dynamic panel estimators, that is, Arellano and Bond (1991) and Blundell and Bond (1998). In contrast to previous aggregate estimates, we employ information from different causes of death from the World Health Organization Statistical Information System (WHOSIS). This data set provides new insights to the pat- terns of mortality, but these data have not been systematically analyzed (with the exception of Becker, Philipson, & Soares, 2005). In the 544 WORLD DEVELOPMENT paper, we find that income growth contributed to the world mortality decline during 1960–90 in non-trivial amounts and that the contribu- tion has not decreased over time as a pure tech- nology transfer would suggest. The contribution of economic development largely varies by cause of death, but, as expected from the epidemiological literature, the contribution of economic development to diseases sensitive to nutrition, 45%, is larger than to diseases in which nutrition has a minimal influence, 25%. Due to the undisputable importance in the decline in mortality, we center our attention on the reduction in infectious diseases as causes of death in less developed countries. 4 The pa- per argues that improvements in economic con- ditions since the 18th century are an important factor behind the initial decline in death rates in developed countries and in the subsequent reduction of death rates in less developed coun- tries. However, as the epidemiological literature suggests, economic development lowers mortal- ity rates through differential effects in infectious disease mortality. The rest of the paper proceeds as follows: Section 2 constructs the stylized facts behind the escape from high mortality for developed countries and summarizes the available evi- dence on the different forces that contributed to the mortality decline. Section 3 considers the case of less developed countries. Due to similarities, most of the analysis of Section 2 follows through for less developed countries as well, although the important differences are highlighted. Section 4 describes the data and the econometric methods to measure the contri- bution of economic growth to the world mor- tality decline during 1960–90 using different causes of death. Section 5 presents the results of the estimation and the estimated contribu- tion of income growth. Section 6 concludes. 2. MORTALITY SINCE MALTHUS High mortality represented one of the most persistent barriers to population growth and economic development in pre-modern econo- mies. Historically, the European population faced life expectancies at birth that never seem to have exceeded 40 years and suffered several declines due to famines and recurrent epidemics (Wrigley & Schofield, 1981). At a point between the 17th and 18th centuries, mortality started to decline and income and population started to increase, contradicting the Malthusian hypoth- esis in which both should have been negatively related. The simultaneous rise of per capita income and population provides important facts for an economic analysis of mortality. It does not seem as a random event that mortality declined first among the countries that first experienced the benefits from per capita income growth and that less developed countries always experi- ence lower life expectancies than developed countries (we will return to this point below). However, it is not obvious that income growth in developed countries increased life expectancy at birth directly because urbanization, a conse- quence of economic development, slowed down the mortality decline of Northwestern Europe and North America since cities had relatively higher mortality schedules than rural areas (e.g., Fogel, Engerman, Trussell, Floud, & Pope, 1978; Woods, 2000, 2003). The association between higher per capita income and higher life expectancy in North- western Europe and North America can be better understood as part of a structural trans- formation in which technological change in agriculture sustains economic growth in non- agricultural sectors but leads to a deterioration in mortality due to urbanization. Since food is an income inelastic good, as agriculture be- comes more productive, less labor is required in food production and more labor can be re- leased to more productive activities. At the same time, higher agricultural productivity im- proves nutrition, lowers susceptibility to infec- tious diseases, and consequently increases life expectancy and population growth whenever the effects of urbanization do not fully offset the gains in agricultural productivity. Although these Malthusian mechanics ap- pear very simple to account for the current state of population and the escape from the Malthusian world, the next sections provide an empirical basis that favors the economic conditions outlined above as the main factors in the escape from high mortality. (a) Facts and implications By the middle of the 20th century, North- western Europe and North America had achieved a new pattern of mortality in which infectious diseases were substituted by chronic and degenerative conditions as the main causes of death, and the modal age of death shifted from childhood to older ages. The timing and geographical distribution of the decline in ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 545 mortality across Northwestern Europe varied, but historical statistics have revealed that Eng- land was the first country to escape from high mortality at the time Malthus published his Es- say on the Principle of Population ( Malthus, 1803). 5 Figures from Wrigley and Schofield (1981) and Wrigley, Davis, Oeppen, and Schofield (1997), and complementary sources show that the secular decline in mortality in England and Wales took place in two waves. The first wave started around 1750 and lasted until 1820, after which mortality stabilized for half a century. 6 The second wave began around 1870 and has not yet ended because mortality at older ages is still declining (e.g., Oeppen & Vaupel, 2002). Since historical sources provide enough information for a broad interpretation of the mortality decline, we propose the following stylized facts: (a) The initial decline in mortality is due to reductions in death rates at early ages and not to sustained increases in the life span of older-age populations. (b) The initial mortality reduction primarily benefited rural areas. Urban mortality remained high due to the urbanization asso- ciated with the Industrial Revolution. (c) Although mortality rates fluctuated more before the mid-18th century, the elim- ination of crisis mortality accounts for only a small fraction of the secular decline in mortality. (a) That mortality at early ages contributed most to the reductions in mortality follows from the observed changes in life expectancy and age-specific death rates. Before 1750, infant and child mortalities were very high and had a considerable impact on life expectancy at birth and overall mortality (Vallin, 1991). To deter- mine the overall mortality reduction, Table 1 computes relative death probabilities (condi- tional on surviving to the beginning of every age range) for England and Wales with respect to a base set in 1750. The table brings out the pre-transition situation clearly. Almost 20% of the babies born failed to survive until their first birthday, and around one-third died before the age of 5. During the first year of life, the prob- ability of death was about six times the level found among children 10–14 years old and about three times the level of children 5–9 years old. Before the mid-20th century, increases in life expectancy in developed countries were ob- tained by a reduction in the number of people dying in early life and not by changes in life expectancy at older ages. Although the initial decline that started during 1700–50 was par- tially reversed during 1800–60, by 1900 mortal- ity before the age of 10 declined by about 40% while old age mortality remained unchanged. Up to 1960, mortality between the ages of 60 and 64 fell by 10%, whereas in 1960, the prob- ability of dying at age 5 was less than 5% of the value in 1700 (see Table 1). 7 Several implications follow from the fact that early life had a predominant role in the mortal- ity decline. A complementarity between longev- ity and human capital investments has been long recognized and studied (Kalemli-Ozcan, Ryder, & Weil, 2000; Meltzer, 1992): higher hu- man capital creates an incentive for a longer life span (in order to increase the time to collect the benefits of the investment) and a longer life span is an incentive for more human capital accumu- lation. However, a direct incentive in terms of life span is not clearly arguable since gains in old age mortality are secondary to infant and Table 1. Relative age-specific death rates (per thousand) Age 0 1–4 5–9 10–14 30–34 40–44 60–64 70–74 Death rates 170.4 107.3 41.1 25.7 48.2 78.1 171.6 341.1 Relative death rates (1750 = 100) 1750 100 100 100 100 100 100 100 100 1800 85 91 63 78 88 73 93 122 1860 88 131 101 95 106 84 134 184 1900 86 71 45 42 63 65 132 125 1930 37 23 26 27 34 35 105 121 1960 13 3 5 6 11 17 89 102 England and Wales, 1750–1960. Source: Wrigley et al. (1997, Tables 6.14 and 6.19) and Case et al. (1962). 546 WORLD DEVELOPMENT child mortality. In fact, a large part of the gains in mortality took place before children could engage in formal education (see Table 1). 8 Also, education and human capital accumula- tion often provide the means for a faster and more effective spread of infectious diseases for children (see, e.g., Miguel & Kremer, 2004). It has also been shown that the scope of changes in childhood nutrition and exposure to disease (as early as in utero) extends well be- yond the improvement of child mortality and into health in later life. As the survey of Elo and Preston (1992) shows (also Mosley & Gray, 1993), some changes in adult and old-age mor- tality can be traced back to conditions experi- enced early in life. If correct, the idea that early life conditions have long-lasting conse- quences for adult and old age mortality is an indication that a life-cycle approach to mortal- ity is needed to fully evaluate the effect of eco- nomic and social changes experienced by children. It would also imply that the large gains in old-age mortality in the second half of the 20th century have been in part the conse- quence of changes experienced by cohorts born during the early part of the 20th century. (b) From antiquity to the early 20th century, urban areas experienced higher mortality than rural areas did. Table 2 presents age-specific death rates for London and England and Wales excluding London. As the table shows, mortal- ity rates in London were more than double the mortality rates in England and Wales. Szreter and Mooney (1998) further demonstrate the ex- tent to which rapid urbanization and rapid city growth created a penalty in England. For example, Szreter and Mooney (1998) show that children born in Manchester in 1841 had a life expectancy of 25.3 years, which was 16.4 years lower than the average life expectancy in Eng- land and Wales and 19.8 years lower than in rural areas. 9 The presence of an urban penalty has been widely documented. Scheidel (1994) corrobo- rates that ancient Rome, the largest city of pre-modern Europe, depended on a constant influx of immigrants to compensate for the ef- fects of high mortality due to infectious dis- eases. In modern times, cities in Northwestern Europe and North America also displayed a substantial penalty in mortality. Parish records for Finland show marked regional differences in mortality (Turpeinen, 1978). France and Sweden exhibit a penalty, as Preston and Van de Walle (1978) and Hedenborg (2000) show. Life expectancy in Paris (Seine) in the 19th cen- tury was 30.8 years compared to a value of 38.7 years for overall France. Compared to Europe, the early 19th-century United States was quite rural and presented relatively low death rates, as Malthus (1803) himself remarked. For the urban US white population, life expectancy at birth was 46 years, while it was 55 years for the rural white population (Haines, 2001). Moreover, cities with populations of more than 50,000 in 1830 (Boston, New York, and Phila- delphia) had death rates more than twice as high as the death rates of rural areas (Fogel et al., 1978). In developed countries, the urban differential in mortality remained positive until the first decades of the 20th century; generalized rever- sals were not observed until after the First World War (Easterlin, 2004, Figure 7.1). The relation between urbanization and mor- tality seems in part responsible for the negative association between rapid economic growth and mortality throughout industrialization. Adult life expectancy in the United States de- clined and adult males became 2 cm shorter within a generation prior to the Civil War when per capita income increased at an annual rate of 1.4% (Fogel et al., 1978). 10 Similar reversals have been documented for continental Europe Table 2. Urban–rural age-specific death rates (per thousand) 1650–99 1700–49 1750–99 Age 0 1–4 5–9 0 1–4 5–9 0 1–4 5–9 England and Wales 179 109 27 196 114 28 168 108 24 England and Wales (except London) 170 95 23 177 91 19 154 88 20 London 260 244 67 342 298 95 276 253 57 Ratio 1.53 2.56 2.98 1.93 3.29 4.93 1.79 2.86 2.87 Note: Age-specific death rates for England and Wales, and London from Wrigley et al. (1997, Table 6.14) and Landers (1992, Table 3), respectively. To compute the rates of England and Wales (without London), we employ London’s share of population from Wrigley (1987, p. 162). ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 547 and Scandinavia, although certain sub-popula- tions in the United States failed to experience a reduction in physical stature with industrializa- tion (populations from the urban middle class such as the cadets at West Point Military Acad- emy as well as slave men but not free slaves, see Komlos & Baten, 2004 for a recent overview). These exceptions, as Komlos (1998) points out, suggest that causes other than a deteriora- tion in the epidemiological environment alone played a role in the decline of height associated with the onset of modern economic growth (we will return to the analysis of urbanization and height below). (c) Only through the large national samples of Wrigley and Schofield (1981) was it possible to assess the effect of mortality crises on total mortality because analyses of local areas overemphasized the role of crises as they were geographically concentrated. Wrigley and Schofield (1981) (also Fogel, 1992) have shown that death rates declined in England and Wales because of reductions in normal mortality and not because of the eradication of famines or mortality crises. 11 Since most crises were con- fined to peripheral areas, they had a small aggregate impact (with obvious exceptions 12 ), and their attenuation explains only a small frac- tion of the mortality decline. For example, although mortality crises started to decline as early as the 17th century, removing crises from crude death rates (CDR) indicates that the cri- ses’ contribution to the overall decline in Eng- land and Wales is less than 10% (Table 3). (b) Understanding high mortality Infectious diseases caused high mortality in pre-modern economies because the general population was both highly susceptible and fre- quently exposed to infectious agents. Chronic malnutrition is particularly important for understanding high mortality because nutri- tional deficiencies increase the susceptibility to infection as well as the prevalence and severity of infectious diseases. Malnutrition is caused by inadequate intakes or excessive energy claims on an otherwise ade- quate diet, but a separate contribution of each factor is difficult to measure even under con- trolled experiments (see Scrimshaw, Taylor, & Gordon, 1968 for a classical study of nutrition interventions aimed at mothers and children in a developing country). Yet, estimates of nutri- ent intakes suggest energy intakes below 2,000 kcals per day in pre-industrial England and Wales with improvements in the quantity and quality of the English diet taking place since the mid-18th century. 13 Associated with such improvement lies the most acceptable explanation for the initial decline in mortality: improved nutrition. The grounds for that con- clusion are twofold: (d) Anthropometric measures with a high predictive value for mortality accurately pre- dict a mortality decline for cohorts born in the 18th century. (e) Prior to any public health intervention or medical innovation, diseases sensitive to nutritional status and adequate nursing started to decline. Higher food availability was essential for the initial mortality decline, but the analysis of ur- ban–rural differences in mortality shows that public health efforts eventually controlled the high levels of exposure to infectious diseases in cities and eliminated the urban penalty dur- ing the 20th century. (f) Public health measures, beginning in the late 19th century, reversed the urban penalty (mainly by the reduction in water and food- borne infections). (d) High infection rates, as both a conse- quence and a cause of malnutrition, compro- mise energy available for cellular growth and provide evidence to assess changes in mortality through anthropometric measures. As Fogel (1994) shows, with the use of a Waaler surface Table 3. Impact of mortality crises in England and Wales, 1541–1871 CDR Crisis CDR Normal CDR Percent contribution of crisis 1541–1600 26.93 1.87 25.06 6.94 1601–1700 27.33 1.57 25.76 5.74 1701–50 29.18 1.20 27.98 4.11 1751–1800 27.07 0.48 26.59 1.76 1801–50 23.99 0.14 23.85 0.58 1851–71 22.42 0.13 22.29 0.58 Source: Fogel (1992, Table 4). 548 WORLD DEVELOPMENT (an iso-mortality risk surface), the historical changes in height, weight, and BMI in England and Wales can be used to measure the role of nutritional gains for the overall decline in mor- tality. According to Fogel’s (1994) calculations, nutritional gains explain 90% of the decline up to 1870 and 50% after 1870. As with changes in life expectancy, pre-mod- ern populations experienced cycles of various durations in physical stature rather than a sin- gle structural break. In modern data, heights in England and Wales reached their lowest point during the 17th century and experienced a recovery after the first quarter of the 18th cen- tury with a decline decades after (there is some disagreement over the exact dates because there was a temporary improvement in the 1820s, see Floud et al., 1990; Komlos, 1993; Komlos & Baten, 2004). For example, Komlos (2006, p. 4) convincingly argues that the initial trends in Floud et al. (1990) ‘‘were not identified accu- rately’’ and suggests, for lower-class English boys, that ‘‘heights declined between the birth cohorts of circa 1770 and those of 1795, in- creased thereafter, and then declined again in the 1830s and 1840s.’’ But the cycles in height are not just a modern feature, because physical stature varied consid- erably over long periods of time. For instance, heights in Europe reached their highest point in the Middle Ages (in the fifth and sixth centu- ries, according to Ko ¨ epke & Baten, 2005) with levels that exceeded physical stature even in 1850 (see Ko ¨ epke & Baten, 2005; Steckel, 2005a for European analyses, and Steckel, 2005b for pre-Columbian populations). Over- all, in an analysis of more than 9,000 sets of hu- man remains, Ko ¨ epke and Baten (2005) show that no long-term trend exists for heights be- tween the first century and the beginning of the Industrial Revolution. Still, as Ko ¨ epke and Baten (2005) show, nutrition seems to have some role in explaining the regional differentials as Northern Europe had the tallest heights accompanied by lower population density and higher protein production per capita (the same case can be made for Australia and the United States in the antebellum, see e.g., Steckel, 2005a). Variations in climate and other influ- ences such as gender and social inequality also seem to have played a role in long-term varia- tions in height (see Ko ¨ epke & Baten, 2005). Evidence for Europe thus suggests that height declined after the Middle Ages and reached its lowest point in the 17th century. The recovery in the 18th century was only short lived because the population’s nutritional sta- tus diminished. Overall, it seems that the 17th century presented the lowest heights in modern times, and while the 17th century ‘‘nadir was never again reached, and a subsistence crisis was ultimately averted, in many cases not until the turn of the 20th century did European heights exceed the levels of the early 18th cen- tury’’ (Komlos & Cinnirella, 2005, p. 3). Multiple reasons explain the modern move- ments in heights and the parallel changes in life expectancy. Baten (2002) shows that colder winters beginning in the late 1750s lowered grain and protein production, leading to reduc- tions in physical stature in southern Germany. Proximity to nutrient production, especially for milk production, had a positive effect on average height (see Baten, 2000–01). Meat con- sumption also contributed to significantly in- crease the heights in the 19th-century France while the early fertility decline in France had a beneficial influence on stature (see Weir, 1997, 1993). An alternative and more direct channel between wages and height could be established in continental Europe and Scandi- navia for some periods (see Baten, 2000–01 where methodological issues are also ad- dressed), but, as noted in the previous sub-sec- tion, after 1820 heights and real wages in England and in the United States diverged, giv- ing rise to the ‘‘antebellum puzzle’’ (see Kom- los, 1998 for a detailed study). A definite analysis on the cause of the decline in height associated with industrialization is not yet available. Due to the inadequate sanitation in cities, urbanization and compositional changes in the population seem to be a first-or- der factor. Still, as not all groups were affected by the decline (see Komlos, 1998), other influ- ences seem also relevant for the decline in heights. Additional factors include changes in food prices and a shift away from protein con- sumption, market integration and the spread of disease affiliated with the development of rail- roads, canals, and steamboats (i.e., Baten & Fertig, 2005), the widening of income inequal- ity, a large influx of unskilled workers into cit- ies, and the allocation of nutritious foods to the market rather than to household consumption (see Komlos & Baten, 2004 for an authoritative review on recent advances in anthropometric history). 14 (e) Along with tuberculosis, some endemic dis- eases particularly sensitive to nutritional status and adequate nursing started to decline in the 18th century prior to any health intervention. ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 549 According to McKeown (1976), the decline of tuberculosis and airborne diseases in general can only be explained by gains in nutrition be- cause no other intervention could have effec- tively contributed to the decline of these diseases. The reclassification of diseases by Woods (2000, Table 8.7) corrects the big emphasis. McKeown (1976) placed on respiratory dis- eases, but it is nonetheless consistent with the prominent role of tuberculosis and mortality from infectious diseases. In Woods (2000), tuberculosis still represents the highest decline of a single condition with a contribution of 35% to the mortality decline during 1860– 1900, followed by scarlet fever and waterborne diseases such as typhus and diarrhea. By the middle of the 20th century, mortality from tuberculosis and other respiratory infections had substantially declined prior to any effective medical treatment. Yet, the analysis of McKeown (1976) pro- vides a limited view in a number of respects. For example, by the synergism between nutri- tion and infection, or the fact that malnutrition is not exclusively determined by diets, airborne and waterborne diseases cannot be treated as independent in an accounting exercise as McKeown (1976) did, see Preston (1975), and Preston and Van de Walle (1978). Harris (2004) revisits McKeown’s thesis and provides the much-needed qualifications. (f) Early ages determined the overall differen- tials in urban–rural mortality and served to illustrate the contribution of public health mea- sures to the mortality transition of cities. 15 Although cause-specific mortality statistics are not available for the initial phase of the mortal- ity decline, the cross-sectional distribution of seasonal patterns in late 19th-century England shows that during 1870–99 infant mortality was higher in cities by a summer peak related to water and foodborne diseases and not by dis- eases sensitive to nutrition, which tend to have a strong seasonality in the winter (see Figures 1 and 2). Changes in the seasonality of infant mortality are particularly useful to examine mortality change because infectious diseases follow well- established seasonal patterns. 16 The seasonal- ity in infant mortality shows the effects of the urbanization that followed the Industrial Revo- lution and how public health interventions con- trolled the gastrointestinal diseases responsible 100 140 180 220 260 300 Winter Spring Summer Fall Infant Mortality Rate (per thousand births) 1586-1677 (Rural parishes) 1813-1836 (Industrial parishes) 1686-1722 (Rural p arishes) 1870-1899 (Industrial p arishes) Figure 1. Quarterly IMR in selected areas. England and Wales, 1586–1899. IMR for 1586–1677 and 1686–1722 from the parishes of Selattyn and Kinneley in Jones (1980, Table 6). Industrial parishes for 1813–36 and the matching registration districts for 1870–99 are from Huck (1997, Table 2). 550 WORLD DEVELOPMENT for the summer peak during the late 19th cen- tury. Direct evidence of cause-specific mortality rates for three industrial and three rural towns in England during 1889–91, provided by Wil- liams and Galley (1995, Table 3), confirms the disproportionate effect of gastrointestinal con- ditions in urban populations. Seasonality changes in infant mortality rates also suggest that a winter mortality decline in rural areas, potentially related to respiratory diseases, started at the end of the 18th century and continued in urban areas but was outnum- bered by a sharp increase in summer mortality in urban areas (Figure 1). A strong seasonality in mortality, with summer as the least mortal season, is a well-established characteristic of pre-industrial England and Wales (Wrigley et al., 1997, Figure 6.24). It is not uncommon in aggregate analyses of population growth to interpret the lack of any downward trend in death rates before the late 19th century as evidence of no mortality decline when a constant mortality rate was actually just the reflection of two offsetting tendencies (see Table 2 and Figure 1). That the pressure of urbanization on mortality disappeared indi- cates that public sanitation had a large impact on reversing the urban penalty in the late 19th century, but it seems very unlikely that public health measures were the main factor behind the initial escape from high mortality in devel- oped countries. 3. THE MORTALITY OF POOR COUNTRIES Differences in mortality within less devel- oped countries exist (Figure 3), but even in the countries with the lowest life expectancy, mortality at the end of the 20th century was well below that experienced by Northwestern Europe in the 18th century. 17 Also, similar to the mortality decline in rich countries, most gains in life expectancy have to be attributed to a lower mortality during early years and not to extended life spans for the old-age pop- ulation. The case of Brazil and India, sum- marized in Table 4, shows once again the disproportionate effect of the mortality decline at early ages. The table also shows that as in the historical experience of developed countries, the age groups more vulnerable to malnutrition and environmental conditions (young children) had the highest proportional decline. Urban–rural differentials have not influenced the epidemiological transition of poor countries 80 120 160 200 240 280 Winter Spring Summer Fall Infant Mortality Rate (per thousand births) En g land and Wales London Five lar g est towns Rural avera g e Figure 2. Quarterly IMR. England and Wales, 1870–99. Data from Huck (1997, Table 2) based on official registration data. The five largest towns are Liverpool, Birmingham, Manchester, Leeds, and Sheffield. ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 551 in a similar way as in developed countries be- cause mortality gains in urban areas exceed by far the gains in the rural counterpart of poor countries: 25 35 45 55 65 75 85 1860 1880 1900 1920 1940 1960 1980 2000 Average life expectancy at birth (in years) 3 DCs (Sweden, France, and U.K.) 2 LDCs (Brazil and Costa Rica) 7 DCs 10 LDCs 29 DCs 136 LDCs Figure 3. Average life expectancy at birth in developed and less developed countries, 1860–2000 (constant samples). Sample sizes in the figure. Data from Arriaga (1968), Keyfitz and Flieger (1986), Preston (1975), World Bank (2000), and United Nations (several years). Table 4. Relative age-specific death rates (per thousand) Age 0 1–4 5–9 10–14 30–34 40–44 60–64 70–74 Brazil, death rates 257.2 161.4 87.0 46.0 91.6 122.6 263.9 437.0 Relative death rates (1890 = 100) 1890 100 100 100 100 100 100 100 100 1920 88 82 83 89 86 82 88 93 1960 41 26 23 24 27 27 47 62 2000 14 6 2 5 13 17 34 44 India, death rates 287.1 186.8 67.4 53.7 113.2 142.4 330.7 517.7 Relative death rates (1900 = 100) 1900 100 100 100 100 100 100 100 100 1920 84 82 91 91 96 91 93 95 1960 52 46 37 17 39 42 52 64 2000 25 13 15 13 15 19 38 54 Brazil, 1890–2000 and India, 1900–2000. Source: Arriaga (1968), Malaker and Roy (1990), Keyfitz and Flieger (1986), and the World Heath Organization (WHOSIS). 552 WORLD DEVELOPMENT [...]... represents the coefficient on urbanization rates * and ** indicate significant values at p < 0.05 and p < 0.10 Investment rates and the black market premium to foreign exchange are standard instru- ments in empirical analysis of economic development (see, e.g., Easterly, 1999; Pritchett ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY & Summers, 1996) As we consider annual changes in mortality, ... capita is as a measure of the standard of living ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 565 20 Inferences from household surveys in less developed countries consistently show the adverse effects of inadequate nutrition on premature mortality and morbidity (Behrman & Deolalikar, 1988; Ravallion, 1987) minimal, and there are suggestions that antibiotics, sulfa drugs, and curative services... and Licandro (2003) argue that mortality for the working age population declined before child mortality and served as an incentive for human capital accumulation and long-term economic growth However, their analysis uses data for Geneva and Venice, so generalizations and extrapolations are difficult In England and Wales, substantial improvements in adult mortality took place during the first half of the. .. second half of the 20th century Between one-third and one-half of the gains in mortality at the youngest ages can be related to the increase in income The estimates based on the two cross-sections tend to be higher than the estimated contribution that results if the coefficients from the dynamic panel estimates are employed The estimates for the sample of less developed countries are also below the estimated... consider the dynamic panel estimates from the world sample and the restricted sample of less developed countries The contribution of income growth to the mortality decline is reported in Table 13 The table shows information for all age groups and for infectious diseases according to sensitivity to nutrition The results confirm the importance of income growth for the mortality decline during the second... support the view that agricultural changes associated with economic development initiated the escape from high mortality and provided the conditions for higher population and higher income in the world As food availability increased, anthropometric and epidemiological evidences indicate that people in developed countries became taller, heavier, and less susceptible to infectious diseases, especially to... countries, but the mortality decline in less developed countries shares important similarities with the escape from high mortality of developed countries, as we show in this paper In both cases, the decline in mortality corresponds to an epidemiological transition that reduced infectious disease mortality, especially child mortality There are multiple channels through which economic development reduced... (Relethford, 1996) Galor and Moav (2002, 2004) also consider lactose and gluten tolerance and the sickle cell trait as examples of mutations in humans but they hardly seem relevant for modern mortality and population change, especially since African populations, having a genetic advantage for low mortality, still experience the lowest life expectancies in the world 4 The mortality decline and the contribution... decline in mortality has outpaced the decline in fertility in every country in the world Although this increase in population is often interpreted as driven by exogenous forces, this paper shows that an important component of the escape from high mortality can be associated with economic development This is perhaps better illustrated in the statistical decomposition provided in the paper And while the contribution... to migrate before 1855, and forced an additional 3 million to migrate during the subsequent five years Even at the end of the 20th century, the population of ´ Ireland remained below the pre-famine level (O’Grada, 1994) 13 Harris (2004) provides a recent overview of the role of nutrition and public health in the mortality decline of England and Wales with detailed accounts of the trends in wages, earnings, . population from Wrigley (1987, p. 162). ECONOMIC DEVELOPMENT AND THE ESCAPE FROM HIGH MORTALITY 547 and Scandinavia, although certain sub-popula- tions in the. favors the economic conditions outlined above as the main factors in the escape from high mortality. (a) Facts and implications By the middle of the 20th